What was failing
BHI Coatings performs Induced Draft Fan Blade Erosion Protection for industrial plants in Alvin and across the Texas Gulf Coast.
An induced draft fan pulls ash-laden flue gas across its blades and housing, and the suspended particulate wears the metal away wherever it strikes hardest. The leading edges of the blades lose profile first, the housing thins behind them, and the loss throws the rotor out of balance.
As that wear spreads, the fan vibrates, moves less gas, and runs the risk of an unplanned trip. Left untreated, the blades and housing keep degrading until the fan has to come out for a full rebuild far sooner than the plant can afford.
How BHI Coatings approaches Induced Draft Fan Blade Erosion Protection
We take the rotor and housing where the metal has been carried away by the gas stream and bring it back. We blast the worn surfaces to clean, profiled steel, then rebuild the lost leading edges and the thinned housing with Belzona 1000 Series composites, working cold so the blades see no heat distortion that would warp the profile or shift the balance. Once the metal is back to shape, we apply an erosion-resistant coating over the blades and the high-wear paths so the new surface takes the particulate instead of the steel. The coating gives the gas a sacrificial face that is easy to renew at the next outage, which is what stretches the run between rebuilds.
Assess and map
We inspect the rotor and housing to locate where the ash-laden gas has eaten the leading edges and thinned the metal, and confirm the wear paths through the fan.
Surface preparation
We grit-blast the worn blades and housing back to clean, profiled steel so both the rebuild and the coating bond properly.
Cold rebuild leading edges
We rebuild the lost leading edges and thinned housing with Belzona 1000 Series composites, working cold so the blades take no heat distortion.
Apply erosion-resistant coating
We coat the blades and high-wear paths with an erosion-resistant system that gives the gas stream a sacrificial face instead of bare steel.
Cure and return to service
We confirm cure and check the finished profile, then hand the fan back ready to run within the outage window.
The result
What Induced Draft Fan Blade Erosion Protection looks like
Repair and protection work of this kind, performed by BHI Coatings crews across the Texas Gulf Coast.
